Tourmaline is a complex borosilicate mineral with a variety of unusual pyroelectric and piezoelectric properties. It is probably best known for its use as a gem stone; however, in recent years, it has begun to find a number of other uses that are in one way or another connected to its unique electrical activity, which results from the presence of permanent electrodes within the crystalline structure. In particular, tourmaline in water produces an electrical discharge which dissociates the water molecule into hydrogen and hydroxyl ions, which in turn produce hydronium ions (H.sub.3 O.sup.+) and hydrated hydroxyl ion (H.sub.3 O.sub.2.sup.-) by their reactions with H.sub.2 O molecules. Both these ions are reported to have surface active properties.
These observations have resulted in the use of tourmaline in a variety of different industrial products and methods. For example, U.S. Pat. No. 5,599,455 discloses a system for water treatment in which tourmaline is used in an ion generator to generate hydronium and hydroxyl ions in the water, with the reported result of "high surface activity" in the water, which is then recommended for use in detergent free washing in washing machines and in cleaning oil-contaminated machinery. In a similar vein, U.S. Pat. No. 5,309,739 discloses a tourmaline coating applied to a surface of a washing machine with the intent of forming hydroxyl ions in the wash water to aid in cleansing. It has also been disclosed (JP 7024444) as being used in powder form in a shower apparatus to treat chlorinated water, so as to alter the chlorine structure, allowing it to retain its water-purifying activity, while reducing the possible negative effects of chlorine.
Tourmaline has also, in connection with its electrical properties, been suggested as being useful in promoting physical well-being. For example, JP 6173162 discloses fabric coated with a film containing tourmaline, which fabric is made into clothing which is said to provide an electrical stimulus to the wearer's skin, to improve the wearer's health. Likewise, JP 8057060 discloses a "health therapeutic tool" based on a substrate incorporating powdered tourmaline and a diode, which tool is applied to the skin to achieve a therapeutic effect.
The use of tourmaline in cosmetics has also been proposed. JP 9194321 suggests the use of very fine tourmaline powder as an antiseptic in cosmetic products. In addition, U.S. Pat. No. 4,857,306 suggests the use of pure powder of semi-precious stones, including tourmaline, as a decorative addition to cosmetic compositions. However, tourmaline has not previously been used in cleansing cosmetic compositions.